Positive reinforcement training (PRT) programs have been implemented in many animal facilities in an effort to refine human-animal interactions. The variation seen between individual animals in training suggests that an animal’s personality may influence certain training methods. Understanding how personality, i.e. individual behavioral profiles, affect the predictability of an animal’s response to training enhances animal selection criteria for research projects, acts as a refinement of animal handling and management methods, and serves psychological well-being. Refining animal selection and research methodologies to include novel ways of interacting with animals in ways that are conducive with their personality, or excluding them when methods cannot be adjusted, improves human-animal relationships, refines the quality of scientific outcomes, and enhances non-human primate well-being. This study will investigate the interactions between personality and behavioral conditioning utilizing rhesus macaques. We will utilize rhesus macaques that have been evaluated as infants through Biobehavioral Assessment (BBA) which is designed to characterize temperament, emotionality, behavioral, and physiological responses in young animals to novel environments. Macaques will be grouped into two training groups (a PRT and a NRT group) based on their past BBA behavioral responsiveness scores (Activity and Emotionality) and trained for four weeks. Additionally, each individual will be tested for response to simulated husbandry procedures by non-training persons prior to and directly after training. We anticipate temperament to influence training in that the level of behavioral responsiveness will correlate with trainability. Likewise, we predict highly trainable animals will show reduced human-directed fear and aggression.

In the United States, more than 30 million mice are used in biomedical research and testing each year. These mice have been isolated from predators for thousands of generations, yet they still respond with fear-like defensive behavior to cat and rat odors. To our knowledge, there has been no study regarding whether or not laboratory mice are innately afraid of humans and, if so, whether we can alleviate human induced fear in mice. After we isolate a human fearful odorant (HFO) that stimulates innate fear in mice, we will look at two methods to make laboratory mice unafraid of human odor. First, neonatal pups will be housed in an environment containing the HFO during their socialization period. Second, adult mice will be exposed to the HFO for desensitization. Aversion, exploratory behavior, and attraction will be measured by the time spent in three arbitrarily assigned sections in a test cage. The anticipated outcomes of the study include the development of a non-invasive method to alleviate human-induced fear response in mice in a way that behavioral stress responses to common husbandry, such as capture, would be reduced. As a result, it would make mice more likely to cooperate than resist, requiring less invasive methods of restraint, thus directly improving their welfare. In addition, due to the reduced frequency of fear-related aggression in lab animals the safety of laboratory staff would improve. Lastly, variables associated with stress in mice would be reduced in biomedical research studies allowing for more accurate results during testing.

Current housing guidelines for mice are based primarily on animal weight or number per cage. Several studies have shown that increasing the number of mice per cage or decreasing space per mouse is not necessarily detrimental, thereby challenging current space recommendations. This study will develop an evaluation system of evidence-based criteria to guide cage size and breeding strategy selection in genetically engineered mouse (GEM) breeding colonies while meeting current animal welfare expectations and to minimize preweaning mortality by refining breeding management. The central hypothesis is that increases in cage size (large versus small shoebox cage) or use of a trio (2 females + 1 male) rather than a pair breeding strategy can positively impact on postnatal care and thus improve reproductive success in many GEM colonies. This study will evaluate health (incidence of death, euthanasia and health problems in male and female breeders), reproduction (litter size, litter number/female, preweaning mortality, productivity index), growth rate (pup body weight at birth and weaning) and behavior (incidence of barbering, fighting, litter cannibalism, nest building) in an estrogen receptor gene-targeted breeding colony (ERKO/BERKO, double knockout) and its wild-type counterpart (C57BL/6) colonies under three experimental conditions (trio in a large shoebox cage, trio in a small shoebox cage, pair in a small shoebox cage). The ERKO/BERKO colony was selected because of its use in multiple research fields. The C57BL/6 mouse was chosen because it is one of the most commonly used mouse strains in research and a common background strain for many GEM models.